Electrically propelled household device



Nov. 6, 1962 c. A. DOSTAL ETA]. 3,061,858

ELECTRICALLY PROPELLED HOUSEHOLD DEVICE Original Filed July 22, 1955 FIG. 2

I III/ Ill/Ill ///I CLARA 4. 005m; '"VENTORS rm/wr 005m.

ATTORNEY Patented Nov. 6, 1962 3,061,858 ELECTRICALLY PROPELLED HOUSEHOLD DEVICE Clara A. Dostal and Frank Dostal, Great Neck, N.Y.; said Frank Dostal assignor to said Clara A. Dostal Original application July 22, 1955, Ser. No. 523,677, new Patent No. 2,950,772, dated Aug. 30,1960. Divided and this application Dec. 31, 1959, Ser. No. 863,245 8 Claims. (Cl. 15-49) The instant application is divided out of our application for patent, Serial Number 523,677, filed July 22, 1955, now Patent 2,950,772, issued August 30, 1960 for "Electrically Propelled Household Vacuum Cleaner.

The instant invention relates to devices, such as vacuum cleaners, floor polishers, waxers, and the like, particularly of the kinds employed in the average household, which, while in the broad category of labor-saving devices, nevertheless still require appreciable physical effort on the part of the user in propelling them from place to place. The effort so required is frequently enough to prevent the use of such devices by the physically handicapped, semi-invalids and convalescents.

It is an object of the invention to reduce to a minimum the physical, generally manual, effort required to operate various devices of the type which roll on, or travel over, the surfaces on which they act, for example, vacuum cleaners, carpet cleaners, floor waxers, floor polishers, scrubbers, scrapers, sanders, lawn mowers, etc., by making the devices self-propellent by a separate motor but more generally by the electric, or other, motor already incorporated in the device for actuating the work performing element or elements thereof.

Still another object of the invention is to provide household devices of such types which are propellable in the forward and in the backward direction selectively under the control of the user.

Still another object of the invention is to provide devices of the type above mentioned with a switching means to initiate and terminate the power propulsion.

Still another object is to provide such devices which can be propelled in both the forward and backward directions at the same speed or with one of such speeds, usually the forward speed, greater than the other.

Still a further object of the invention is to provide vacuum cleaner devices with driving means supplying substantial assistance in making turns.

Another object is to provide increased traction between the rotatable elements of the drive of such devices.

Still another object of the invention is to provide such a device in which the propelling drive assumes a neutral position when not in operation.

Still a further object is to reduce the amount of time spent by even normal persons in performing the tasks for which the device, for example, a vacuum cleaner or a floor waxer and polisher, is designed by incorporating in the device the power drive unit of our invention.

We accomplish the foregoing, and other, objects of the invention by providing a set of floor engaging rollers which is power driven by a system of driving rollers including at least one elastic belt and pulley between such set of rollers and a driving motor mounted on the device, or by any other system transmitting rotary motion, such as sprockets, chains, gearing, etc., driven by such motor. Where the motor is an electric motor, it is energized by providing a normally open switch in the handle of the device at the region where it is usually held, which switch, on grasping the handle about the switch, is closed to connect the line supply to the motor. With the motor energized, when the handle is pulled, the power transmission is so connected to the set of power driven floor engaging rollers that the device is propelled rearwardly,

whereas when pushing on the handle, it is so connected thereto as to propel the device forwardly. The means for shifting the direction of power transmission includes a transversely aligned pair of levers to one end region of which the lower end of the device handle is pivotally connected, the pair of levers supporting one shaft of the power driving unit. This lever supported shaft, on which the power driven floor engaging rollers are mounted, may be displaced a limited amount from the true transverse direction of the device to enable making power turns by either making the levers of thin material so that they are flexible inserts in the levers. The main portion of the weight of the device is carried by these levers so that the rotatable elements of the drive which are longitudinally movable in the device tend to assume a neutral position in the unoperated position, since in the operating positions of the levers the other portions of the device are raised relative to the power driven floor engaging rollers.

Our instant invention will be more readily understood from the following detailed description of an illustrative embodiment thereof, in the form of power drives for vacuum cleaners of the upright type, when read in conjunction with the appended drawing in which:

FIGURE 1 is a somewhat simplified elevational side view of a vacuum cleaner incorporating an illustrative embodiment of the driving unit of our invention, in which the parts of the vacuum cleaner not essential to the understanding thereof have been omitted, the driving rollers of which are aligned on a pair of levers rotatably supporting the brush roller, the levers being pivotable to engage one or the other set of the directional drive rollers with the floor engaging rollers; and

FIGURE 2 is a top view of the driving unit of FIG- URE 1.

The vacuum cleaner incorporating an illustrative embodiment of our invention, comprises essentially a formed housing 1, within which the motor 2, by way of a drive shaft 3, drives the brush 4 in the mouth of the suction tube of the cleaner, as also at least one suction fan in such suction tube which opens, into a dust collector or bag. The fan on rotation creates suction at the mouth of the tube, thereby drawing dust laden air at such month into the tube and propelling it to the dust collector or bag, in well known manner. Since these latter elements are all well known in the art, only those essential to the disclosure and understanding of the instant invention are shown and referenced. The rear portion of the housing 1 is provided with a pair of transversely aligned rollers 5, 5', so supported therefrom that when the brush and these rollers are on the floor, the drive shaft 3 is in a predetermined position, for example, horizontal.

It is to be understood that the parts so far enumerated may be of any prior known type, and also that a primed reference character means that a like element is transversely opposite the non-primed element in the embodiment.

The self-propelling unit of the embodiment has a pair of frame members 6, 6' supported within the housing 1, each frame member being spaced from the lateral walls thereof and extending longitudinally therein. The brush 4 is fast on the brush shaft 7 which is rotatably supported at its end regions in the forward portions of the frame members 6, 6', the brush side of the embodiment being designated the forward end in this application. The brush is driven by way of pulley 8 integral with the midregion of the shaft 7, a belt 9, and the motor shaft 3, the brush motion being in the clockwise direction as viewed in FIGURE 1 such that the tufts of the brush sweep forwardly on the floor at all times irrespective of the direction of the device itself is moving.

The brush shaft 7 is supported by a pair of levers 10,

and the forward drive rollers 11, 11' are integrally mounted on the ends of the brush shaft. The brush shaft also carries the integral intermediate drive rollers 12, 12 of which the cylindrical surfaces engage those of the rearward drive rollers 13, 13' rotating the latter in the opposite direction. to provide means for different forward and reverse speeds. The stub shafts 14, 14' of the rearward drive rollers 13, 13 are supported in the levers 10, 10' above the brush shaft 7. At the regions of the levers aligned horizontally with the line of contact of the rollers 12, 12 with the rollers 13, 13', the levers are pivoted on pins 15, 15' to the frame members 6, 6, the upper ends of the levers 1i), 1%) being pivoted to the forked ends 16, 16 of the device handle 17. The floor roller shaft 13 is fixedly supported in the frame members 6,6 at such distance that the cylindrical surfaces of the floor rollers 19, 19 rotatable on shaft 18, are engagea'ble by the forward drivers 11, 11' when the handle is pushed, and by the rearward drive rollers 13, 13' when the handle is pulled. It will be noted the pivot pins 15, 15 are so located on pulling the handle, that the forward drive rollers, driven clockwise, will be suificiently moved away from the floor rollers to permit the rearward drive rollers to engage the outer cylindrical surfaces of the floor rollers and cause them to rotate clockwise and move the device rearwardly. In like manner, the forward motion of the device is obtained by pushing the device handle forward, thus causing the drive rollers 13, 13' to disengage from the floor rollers, and the drive rollers 11, 11, still driven clockwise, to engage the floor rollers and rotate them counterclockwise to move the device forward. In the event that equal forward and backward speeds are required, the diameter of rollers 11 and 12 should be of the same size, in fact, in this situation the two rollers can be one.

A pair of matched springs 20, 21 and 20, 21' each spring of which is anchored at one end in the frame member 6, 6 and connected with its other end to the upper ends of levers 10, 10, returns the levers 11, 11 to a neutral position when the handle 17 is released.

An electric line switch 22 which is spring biased to its open position, is provided in the handle 17 at the upper region thereof where it is normally grasped by the user; of which switch the blade, appropriately insulated, extends outwardly from the handle. When the user encircles the handle at that region with his hand, the switch blade is depressed to close the circuit, connecting the line current by way of the usual plug to the motor 2.

In operation, when the handle 16 is pushed forward, the levers 11, 11' pivot about brush shaft 7 thereby moving the forward drive rollers 11, 11' against the outer cylindrical surfaces of floor-engaging rollers 19, 19 and rotating the latter counter-clockwise to propel the vacuum cleaner forward. When the handle 16 is pulled rearwardly, the forward drive rollers disengage from the floor rollers and the rearward drive rollers 13, 13' are swung rearwardly to engage the outer cylindrical surfaces of floor rollers 19, 19 thus propelling the vacuum cleaner rearwardly.

The levers 10, 10' being made, as above stated, of thin material flexible in torsion, the vacuum cleaner may be driven about a turn. For example, assuming a turn is to be made downwardly to the left in the forward direction in FIG. 2, handle 16 is pushed and deflected upwardly to the right, that is, in the direction opposite the desired turn, this constituting a quite usual and normal maneuver. By so doing fork 16 pushes lever 10 forwardly, thereby engaging forward drive roller 11 to floor roller 19, while fork 16 pulls lever 10' back, thereby engaging rearward drive roller 13 to floor roller 19', thus propelling the vacuum cleaner forwardly in a left turn.

It appears obvious that the speed at which the household device, in which our power drive unit is incorporated, is propelled forwardly or rearwardly, is a matter of relative dimensioning of the rotatable elements of the The purpose of rollers 12, 12 is drive. While the disclosed embodiment has the drive and floor rollers between the respective frame member and its adjacent lateral wall, the rollers may be positioned between the frame members and the latter can be the lateral walls per se of the device casing. Furthermore, the motor driving the power drive unit of the invention, instead of being the motor built into the household devce to drive other elements thereof, may be a separate motor individual to the power drive.

Various other changes, for example replacing the levers by slide members, will suggest themselves to the skilled worker in the art without departing from the teaching of our invention. The embodiment shown and described is by way of illustration solely, and is in no way limitative, our invention being as broad as the prior art permits and as defined in the appended claims.

What we claim is:

1. A propelling unit for household devices rollable on floors comprising a plurality of floor engaging rollers, a pair of drive rollers positioned vertically relative to each other, means for selectively engaging either drive roller of the pair with at least one floor engaging roller and disengaging the other drive roller of the pair from the floor engaging roller, motor means for rotating the drive rollers, and a handle extending from the device of which one end is connected to the selective engaging means so that on pushing the handle that drive roller of the pair which will propel the drive forward engages the supporting roller and so that on pulling the handle that drive roller of the pair which will propel the device rear ward engages the floor engaging roller.

2. A propelling unit according to claim 1 in which a pair of balanced, mutually opposing, springs bias the selective engaging means in the absence of a push or a pull on the handle and in the absence of energization of the motor to a neutral position at which both drive rollers of the pair are disengaged from the floor engaging roller.

3. A propelling unit for household devices rollable on floors comprising a casing having side walls, a first shaft extending transversely across the casing, a floor engaging roller at each end region of the first shaft, a pair of elongated levers each pivoted at its intermediate region to a respective side wall in transverse alignment, a second shaft of which the ends are rotatably supported in a portion of each lever below the pivoted intermediate region, a stub shaft extending from each lever and vertically aligned with the second shaft, a pair of drive rollers of each end of the second shaft, a drive roller on each'stub shaft in rolling frictional engagement with one'corresponding drive roller of the pair at that end of the second'shaft, each lever being pivoted at the region thereof in alignment with the line of contact of the drive rollers on the stub shafts with the therewith engaging drive rollers of the second shaft, a handle extending from the casing, and means for selectively engaging one drive roller of each pair on the ends of the second shaft and the drive roller of the stub shafts with the floor engaging roller to propel the device forward, rearward or in turns on energization of the motor as the handle is pushed, pulled or laterally defiected.

4. A propelling unit for household devices rollable on floors having an elongated casing with a longitudinally extending side frame, a lever pivoted at its intermediate region to the frame member, a first shaft rotatably supported in the lever at its lower end region, a first drive roller integrally on the first shaft, an intermediate roller integrally on the first shaft, a second shaft supported in the lever at the region above that at which the lever is pivoted, a second drive roller rotatable on the second shaft and at all times in rolling frictional engagement with the intermediate roller, a handle extending from the casing, a pivotal connection between the upper-end region of the lever and one end of the handle, motor means for driving one shaft of the first and second shafts, a third shaft supported in the frame member, and a more gaging roller rotatable on the third shaft and so positioned that on pushing the handle one of the first and second drive rollers which propels device forward engages the floor engaging roller and on pulling the handle the other of the first and second drive rollers which propels the device rearward engages the floor engaging roller.

5. A propelling unit according to claim 4 in which a pair of balanced springs, one attached to each longitudinal edge region of the lever and anchored in the frame member below the pivoted region of the lever, balance the lever in a neutral position with the drive rollers disengaged from the floor engaging roller when the handle is neither pushed nor pulled.

6. A propelling unit according to claim 4 in which a cylindrical brush is integral with the first shaft and the motor drives the first shaft counterclockwise at all times.

7. A propelling unit for household devices rollable on floors comprising an elongated casing having side walls, a thin elongated lever twistable in torsion pivotally supported at its intermediate region in the lower portion of each side wall, a first shaft rotatably supported at its ends in the lower end regions of the levers, a first drive roller and an intermediate roller integrally on the first shaft at each end thereof, a pair of aligned stub shafts each supported at its outer end in a respective lever above the region at which the lever is pivoted, a second drive roller rotatable on each stub shaft and at all times in rolling frictional contact with the intermediate roller at the corresponding end region of the first shaft, a handle extending from the casing and having a forked end, a linkage between the respective forks of the one end of the handle and the upper region of the respective levers, a motor for rotating the first shaft, a second shaft supported in the casing side walls, and a floor engaging roller rotatably on each end region of the second shaft and so positioned that on pushing the handle forward the drive rollers of the first or stub shafts rotating in the direction to propel the device forward are engaged to the floor engaging rollers, on pulling the others of the first and second drive rollers are engaged to the floor engaging rollers to propel the device rearward, and on deflecting the handle transversely one first drive roller engages its cooperating floor engaging roller while the second drive roller on the stub shaft on the lever pivoted on the opposite side wall engages its cooperating floor engaging lever to propel the device in a turn in the direction opposite to that in which the handle is deflected.

8. A propelling unit according to claim 7 in which the motor rotates the first shaft counterclockwise and a normally open switch, electrically connected to the motor and having an insulated throw-blade, is positioned at such region of the handle that on grasping and encircling that region of the handle the switch is closed to energize the motor.

References Cited in the file of this patent UNITED STATES PATENTS 1,965,787 Adams July 10, 1934 2,540,717 Diether Feb. 6, 1951 2,897,645 Veillette Aug. 4, 1959 FOREIGN PATENTS 623,790 Great Britain May 23, 1949 

